Hinge mounting



G. D. PAGON HINGE MOUNTING June 10, 1947.

Filed Sept. 17, 1943 3 Sheets-Sheet l INVENTOR GarrefiDPagon BY l ATTORNEY June 10, 1947. G. v|: PAGON 2,421,960

HiNGE MOUNTING Filed Sept. 17, 1943 3 Sheets-Sheet 2 5i 5O Flaw.

41 Li I INVENTOR I darrefiD. Pagan v ATTORJYEY June 10, 1947. PAGON I 2,421,960

HINGE MOUNTING Filed Sept. 17, 1945 3 Sheets-Sheet 3 V INVENTOR GarrefiDPayofl BY fi ATTORNEY Patented June 10, 1947 UNITED STATES PATENTVOFFICE 2,421,960 HINGE MOUNTING Garrett D. Pagon, Conshohocken, Pa, assignmto The Budd Company, Philadelphia, Pa., a corporation of Pennsylvania I Application September 17, 1942, seen No. 502,750

8 Claims. 1

This invention relates to hinge mountings for aircraft control airfoils and has for an object the provision of improvements in this art.

One of the particular objects of the invention is to provide a hinge assembly which will strengthen the airfoil where it is recessed on the leading edge to receive the hinge bracket.

Another object is to provide a hinge mounting which can be made as a separate subassembly and easily joined to the airfoil assembly.

Another object is to provide a strong construe tion at the ends of the nose sections of the airfoil on either side of the hinge bracket recess.

Another object is to provide a strong connection between the nose ribs and spar and the hinge assembly.

Another object is to provide an end rib construction which is uniform with the construction of the airfoil as a whole.

Another object is to provide a hinge box assembly which transmits hinge pin strains rigidly and effectively into the airfoil spar structure.

Another object is to provide a hing box assembly which effectively transmits torque from one spar section to another across the hinge bracket recess.

Another object is to provide a hinge box assembly which is strong and rigid transversely, that is along the length of the adjacent spar.

The above and other objects and advantages of the invention will be apparent from the following description of an exemplary embodiment thereof, reference being made to the accompanylng drawings, in which:

Fig. 1 is a plan view of a contro1 airfoil hinged to a fixed airfoil by structure embodying the present invention;

Fig. 2 is an enlarged verticalchordwise section taken on the line 2-2 of Fig. 1;

Fig. 3 is a vertical spanwise section taken on the line 33 of Fig. 2;

Fig, 4 is a plan view, partly in section, taken on the line 4-4 of Fig. 2;

Fig. 5 is a perspective section of the whole assembly from the rear; and

Fig. 6 is a perspective of the basic hinge box subassembly alone.

The present hinge construction may be used in many locations and is illustratedherein in connection with an elevator 10 and stabilizer H to which it is hinged. For purposes of identification, the stabilizer tips are designated as l2, the fuselage tail cone as l3, the fin as M, the rudder as I 5, and the elevator trim tabs as. l6.

upon brackets 2| attached to the rear spar 22 of the stabilizer. Considerable of the details of the bracket and stabilizer structure are shown in Fig, 2 but they are not important here. The prese'rit invention centers about the hinge pins 23 and the hinge and elevator structure associated therewith. The recesses or slots 24 for the brackets 2| in the leading edge or nose of the elevators and the hinge boxes behind the recesses are generally indicated in Fig. 1 and shown in more detail in Fig. 2. In Fig. 2 it is also shown that the leading edge, along with the other parts of the airfoil is covered with fabric in the final assembly; but the leading edge hasically is formed of a metal frame and a covering thereon and will be so discussed herein. The elevator operating mechanism is shown in dotted lines and is generally indicated by the numeral 26-.

Thecontro'lairfoil HI includes the leading edge or nose portion 30, the spar 40, and the trailing edge including ribs having chord members 56 secured to the rear of the spar by gussets 5|.

The nose 30 is made inlongitudinal segments divided by the recesses 24 and each segment is composed of half-she'll subassemblies which are overlapped intermediate'ly along mating parts and welded together. Each half-shell comprises a skin sheet 3| skin stifieners or stringers 32, a larger 'stifi weighting nose stringer 33, and rib elements 34. At the ends full-web rib elements 35 are provided. Th nose stringer 33 is welded through its flange 33a to the skin sheet and rib elements of one half-shell in the pre-assembly stage and welded through its inturned channel flange 33b to the skin sheet and rib elements of the other half-she'll in the later assembly stage. The rib element webs are welded together at 34a and 35a along overlapping web portions when the half-shells are secured together. The space at the front of the nose assembly is open for welding along the flange 33b; and the rear end is completely open for welding the rib webs 34a and 35a tog-ether. At some stage of assembly up to this point,- the rib elements 35 have welded thereto inclined tie members 31 which extend out from the rear end. They are secured on the sides of the webs away from the recesses 24 to leave the recess space free and unobstructed for movemerit of the airfoil nose relative to the brackets 21.

The spar vM includes a plurality of web elements M and continuous runnin cap strips or chord members 42. The webs are formed with Each elevator is hinged on a hinge line 201 56 lightening openings Ma and spaced stiffening a ts 1,966

3 struts 43 adjacent the front ends of the trailing rib chords 50. The struts, rib chords, and the gussets 5| are all welded together to form a joint after the spar has been secured in position. There are other stiffening struts 44 which are secured to the spar, the struts 44 having side depressions 44a which are adapted to receive the tie members 31. If desired and as shown, inserts may be provided for the struts 44 to carry the depressions 44a to allow the main part of the struts to be welded to the spar web in pro-assembly and to permit the ends of the tie members 3'! to be pushed through the web when the spar is secured in position. When'the spar is pushed into the rear end of the nose segments, the outer flanges of the Z-shaped cap strips 42 are welded to the skin sheets 3|. The inturned flange of the cap strips is flattened at the trailing ribs and hinge boxes to lie in the plane of the main flange as at '46.

The hinge boxes 60, with which the present invention is particularly concerned, may now be placed and secured. They are placed by pushing them up between the tie members 31, there being two tie members on either side. They are secured by welding them on the sides to the facing flanges of the tie members 31 and on the front edge through facing flanges of the struts 44. Then the cover plates 41 and 48 are placed and welded. They leave a small open space 49 between. their ends on each side for inspection and access.

The structure and mode of assembly of the hinge box 66 is of particular interest. Each box includes a pair of parallel central webs 6| which have inclined side edges 61a which are in general parallel to the lines to be taken by the inclined tie members 31. The webs are apertured to receive cupped bearing members 63 having flanges 63a disposed outside the Webs GI and welded thereto. The cupped members are vertically elongated to extend as near as possible to the tie members 37 and thus form a rigid connection back to the spar 40. The rear ends of the webs 6| are flanged outwardly at 6H) for welding to the cover plate 48.

The box webs 61 are secured together behind the cupped bearing members 63 by a tubular connector 64 of large diameter, the connector being formed of a central tube 64a and flanged end tubes 64b welded to the central tube along the barrel and to the interior of the webs 6| around the flanges. This telescopic arrangement provides adjustment during assembly of the parts to permit the distance between tube ends, and hence the distance between side plates, of the hinge box to be accurately gauged without having to preform parts to precise length, Heavy washers 65 are welded inside the cupped members 63 to form substantial bearing support along with the metal of the cupped members for the hinge pins 23.

The basic hinge box sub-assembly as above described may be used for a great many different locations regardless of varying dimensions of airfoil at their selected points of installation. To accommodate for a fit at different locations, supplemental web plates 66 are overlapped with the edges of the webs 6| and welded thereto, the supplemental plates being of different sizes for difierent locations. box sub-assembly before it is assembled with the spar. They are provided with rear flanges 66a and side flanges 66b and 660 for welding to the cover plates 41 and 48 which are later applied.

They are secured to they The described structure provides a very strong hinge joint which reinforces the airfoil at the nose recess or slots which are points of normal weakness and a source of much trouble heretofore. The method of assembly aid materially in speed of production, particularly by welding equipment.

While one embodiment has been described in detail, it will be understood that the invention may have various embodiments within the limits of the prior art and the scope of the subjoined claims.

What is claimed is:

1. In an airfoil construction in combination, a leading'edge portion having a hinge bracket slot extending back for a distance from the front edge, a spar-like structure extending across the rear end of the slot, said spar-like structure having a hinge bracket slot aligned with the airfoil slot, and a box structure forming a strengthening bridge across and behind the spar slot, said box structure comprising spaced sides connected by a rigid torque tube of a length only to span the space between said sides.

2. In an airfoil construction in combination, a leading edge portion having a hinge bracket slot extending back for a distance from the front edge, a spar-like structure extending across the rear end of theslot, said spar-like structure having a hinge bracket slot aligned with the air foil slot, and a box structure forming a strengthening bridge across and behind the spar slot, said box structure comprising spaced sides connected by a rigid. torque tube of a length only to span the space between said sides, and said spar-like structure comprising struts on the sides of the slot to which the sides of the box structure are secured.

3. In an airfoil construction in combination, a leading edge portion having a hinge bracket slot extending back for a distance from the front edge, a spar-like structure extending across the rear end of the slot, trailing ribs secured to the airfoil and spar-like structure at a distance on each side of the slot, a box structure secured behind the spar-like structure forming a strengthening bridge across the slot at its rear end, said box structure comprising spaced sides connected by a rigid torque tube, and gusset plates on each side of the airfoil forming a connection between the leading edge of the airfoil, the spar-like structure, the trailing edge ribs, and the torque box structure sides.

l. In an airfoil construction incombination, a leading edge portion and an aft spar formation forming the main strength structure of the airfoil, the leading edge being slotted for hinge means completely through its depth back to the spar formation and including parallel closing plates on each side of the slot extending from the front back to the spar formation, the spar having a slot forming an extension of the hinge slot between spar chords which run across the slot, and a torque box including spaced sides and a short torque tube connected therebetween secured to said spar formation across the slot to provide torsional strength across the slotted leading edge portion.

5. In an airfoil construction in combination, a leading edge portion and an aft spar formation forming the main strength structure of the airfoil, the leading edge being slotted for hinge means completely through its depth back to the spar formation and including parallel closing plates on each side of the slot extending from the front back to the spar formation, the spar having a slot forming an extension of the hinge slot between spar chords which run across the slot, and a torque box including spaced sides and a short torque tube connected therebetween secured to said spar formation across the slot to provide torsional strength across the slotted leading edge portion, the torque box sides being aligned with and disposed behind said closing plates, and elongated tie members overlapping and connecting said box sides and closing plates.

6. In an airfoil construction in combination, a hollow edge portion provided with a hinge bracket slot extending back for a distance from the front margin for the full thickness of the airfoil, reinforcing elements arranged transversely of the airfoil thickness at each side of the slot, a bridge box structure including side plates, and a rigid torque tube secured between the side plates, the torque tube being of a length only to span the space between the side plates, the box with its rigid torque tube forming a strong unitary structure secured, together with cover and rear plates therefor, in the airfoil with its side plates in continuation of the transverse reinforcing elements and the interior of the box forming an unobstructed continuation of the slot back to the torque tube, and hinge means for the airfoil within the slot mounted between the side plates forward of the torque tube, the box with its torque tube forming a bridging structure across the slot of a strength to compensate for the weakness in torque caused by providing the slot in the airfoil.

7. In an airfoil construction in combination, a hollow edge portion provided with a hinge bracket slot extending back for a distance from the front margin for the full thickness of the airfoil, reinforcing elements arranged transversely of the airfoil thickness at each side of the slot, a bridge box structure including side plates, and a rigid torque tube secured between the side plates, the torque tube being of a length only to span the space between the side plates, the box with its rigid torque tube forming a strong unitary structure secured, together with cover and rear plates therefor, in the airfoil with its side plates in continuation of the transverse reinforcing elements and the interior of the box forming an unobstructed continuation of the slot back to the torque tube, and hinge means for the airfoil within the slot mounted between the side plates forward of the torque tube, the box with its torque tube forming a bridging structure across the slot of a strength to compensate for the weakness in torque caused by providing the slot in the airfoil, said torque tube having overlapping portions which are connected in adjusted relation according to the spacing required between said side plates.

8. In an airfoil construction in combination, a hollow edge portion provided with a hinge bracket slot extending back for a distance from the front margin for the full thickness of the airfoil, reinforcing elements arranged transversely of the airfoil thickness at each side of the slot, a bridge box structure including side plates, and a rigid torque tube secured between the side plates, the torque tube being of a length only to span the space between the side plates, the box with its rigid torque tube forming a strong unitary structure secured, together with cover and rear plates therefor, in the airfoil with its side plates in continuation of the transverse elements of the slot and the interior of the box forming an unobstructed continuation of the slot back to the torque tube, and hinge means for the airfoil within the slot mounted between the side plates forward of the torque tube, the box with its torque tube forming a bridging structure across the slot of a strength to compensate for the weakness in torque caused by providing the slot in the airfoil, said hinge means including deep hinge cups extending inwardly from said side plates and rigidifying them to transmit torque to said torque tube without buckling of the side plates.

GARRETT D. PAGON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,334,848 Thieblot Nov. 23, 1943 2,254,304 Miller Sept. 2, 1941 2,312,546 Hazard et a1. Mar. 2, 1943 2,262,606 Hardman Nov. 11, 1941 FOREIGN PATENTS Number Country Date 441,102 Great Britain Jan. 13, 1936 446,260 Germany June 27, 1927 366,079 Great Britain Jan. 25, 1932 

